滴水湖表层水体细菌多样性特点初步探究

上海市浦东新区滴水湖自建成后,围绕滴水湖水体质量的研究很多,但是滴水湖水体总体细菌多样性特点的研究尚未见报道。本研究结合16S rRNA基因变性梯度凝胶电泳、16S rRNA基因宏基因组学分析的方法来初步探究滴水湖表层水体细菌的多样性特点,以及滴水湖中粪便污染指示菌、致病菌、条件致病菌和水体富营养化典型菌等的存在性和分布情况。研究结果可以说明滴水湖表层水体在采样期内的细菌多样性:(1) 5个水体样品共获得428个OTU,属于17个细菌门,39个纲,81个目,130个科,191个属,282个种。(2)湖水中以放线菌门(Actinobacteria)、蓝藻门(Cyanobacteria)、变形菌门(Proteobacteria)、拟杆菌门(Bacteroidetes)、疣微菌门(Verrucomicrobia)、浮霉菌门(Planctomycetes)为优势门,占总序列数的97%。(3)在宏基因组中没有检测到水体粪便污染指示菌等相关的序列,在属的水平没有发现沙门氏菌属(Salmonella)、链球菌属(Streptococcus)等致病菌或条件致病菌,只有极少量的序列属于志贺氏菌属(Shigella,0. 1%)。滴水湖表层水体中蓝藻主要为聚球藻属(Synechococcus),没有发现富营养化水体中容易出现的水华蓝藻的序列。可知滴水湖表层水体的细菌多样性特点与淡水湖泊典型细菌多样性特点类似,湖水中没有检出水体污染菌,目前也没有证据表明有蓝藻暴发导致水华的倾向。

Preliminary exploration of bacterial diversity in surface water of Dishui lake, Shanghai

Dishui Lake(DSL) has received a great deal of attention since it built, there are many researches on the quality of water in it, but the research on the bacterial diversity overall was insufficient. Therefore, this study combined 16S rRNA gene denaturing gradient gel electrophoresis (DGGE), 16S rRNA gene metagenome and bioinformatic analysis to understand bacterial diversity and community structure in surface water of DSL, including water fecal pollution indicator bacteria, water eutrophication typical bacteria, pathogens and conditional pathogens. The results show that:bacterial diversity in these 5 water samples can represent it in surface water of DSL at sampling time. 428 OTUs have been clustered from 5 DSL water samples and belong to 17 phyla, 39 classes, 66 orders, 130 families, 191 genera and 282 species. Actinobacteria, Cyanobacteria, Proteobacteria, Bacteroidetes, Verrucomicrobia and Planctomycetes are six dominant phyla in these 5 samples and account for 97% of total bacterial sequences in these samples. Except for a few sequences of Shigella (0.1%), sequences of water fecal pollution indicator bacteria, Pathogens and conditional pathogens were not found in metagenome. In conclusion, the characteristics of bacterial diversity in surface waters of DSL are similar to those of typical freshwater lakes and there are no water-contaminating bacteria detected in the lake, and there is no tendency that blue algae will cause blooms.